Waste spray collector



July 11, 1950 A. 0| STEFANO WASTE SPRAY COLLECTOR 3 Sheets-Sheet 1 Filed Feb. 5, 1946 VII/11111111111,villi/111% INVENTOR Albert DiSlefwzo W ATTORNEY A. D] STEFANO WASTE SPRAY COLLECTOR July 11 1950 s Sheets-Sfieet 2 Filed Fkb. 5, 1946 INVENTOR Albert Di Stefano AT TO RN EY A. D! STEFANO WASTE SPRAY COLLECTOR July 11, 1950 3 Sheets-Sheet 3 Filed Feb. 5, 1946 R O T N E V N T.

ATTO RNEY Patented July 11, 1950 UNITED STATES PATENT OFF-ICE (WASTE SPRAY COLLECTOR Albert "'Di Stefano, Philadelphia,-Pa. nppiicaetnrebmary 5, 1946,Serialal\lo.w645,-506 1. 4 Claims. (01. 299-4140) l invention relates-generallyto the, class of '.1liquid diffusing and spraying apparatus-and {is directed primarily to improvements in paint spraying machines.

zlnthe-useofpaintisprayers-or paint, guns where t the paint-or lacquerprother coating material, is projected in a finespray from a nozzle under air pressure, atconsiderableamount of vapor or mist fist-developed around thesurface against which the coating material is projected so that the user of the machine lis exposed to the necessity ;-of breathing insuch said-mist or detriment.

vapor to his Various types of apparatus have been devised dol: collecting thewmist or vapor developed in this manner but such devices are, usually designed as separate units .fromthe-spraygim, to be conunectcd or attached thereto ,for use-and disconnected therefrom whenthe spraying operation is t-GOII119ltd and such attachmentsare clumsy and awkward to use and materially interfere with the ease oroperation of the spraygun.

v A principal object of the preesnt, invention,

Another andimore specific object is to provide a spray or :paint gun attachment iii-which use is made of: a portion of theair delivered to the gun, forsetting up a reverse fiowoi air through ta filtering medium whereby-thesmist or vapor which develops aroundthe surfaceheing coated, is drawn into the device and removed .from the air, the air being-discharged rearwardly the gun and the extracted coating substance being collected in a receptacleprovided tor the purpose.

7 Another object of the invention is to provide ,a modified paint spray gun with a vapor or,.mist

collector wherein rearwardlyoirected air jets are employed which receive air from the supplyiwhich operates the gun, to-set up .inand through. a

chamber enclosing thepaint spray, a reverse .tlowoi air and discharge the same irearwardly t n-omthe gun, such reverse iiowvof airheinfg drawn through a filtering material so that the paint or ,cther coating material which .it may carry is effectively removed therefrom, thus maintaining the air around the user of theispray'gun, clean and tree of anypaintparticles.

'A -stil l further obiect of theinven-tionis toprm aide aspray gunstructnrehaving .an-air cleansing l Figure 7 ,a sectional, view corresponding means associated therewith, witha novel control valve mechanism whichis entirely under the conttrol ofa single trigger element for the supplying of the necessary air under pressure 'to the spray nozzle and to the jet from which air is ejected in the reverse direction to the spray nozzle and within a vfunnel unit to cause the spray laden air to be drawnthrough a filtering element.

, Stillanother object of the invention is to provide in a spray gun of the character above'stated, a novel valye mechanism under the control of. .a single operating trigger, for delivering air to the two oppositely directed ietsornozzles, withmeans operated by asing-le ,fi-nger control tor varying the sizesof the valve apertures through which the air ,pa'sses, upon actuation of the trigger, to the spray nozzle andto the tair jets. Q

other objects and advantages of the present inventionwillhecome apparent as the description .of the same proceeds and the invention Willa-be -,best understood-home consideration of the following detailed description taken in connection with the accompanying drawings iorm'inga part of the specification, with the understanding, how- ;ever, that thelinventionis not confined to astrict oonformity with .the is'howing of the drawings .but

maybe changed or modified so long as such changes or modifications mark no material.=de-

parture from the salient ,features of the invention as expressed in the appended claims.

In the drawings:

Eignre i is va view in side elevation of a spray gun equipped withga waste spray collector constructed in, accordance with the present {invensubstantially \on the line '3-I3- of Figure 7 1.

' Figure- 4 iso. transversesectional view taken substantial-1y on theline l-Aof Fi ure I.

Figure 5 is a view. partly in horizontal section and partly in top plan of the casting whichiorms the body or lframe of the l-paint gun.

a .Figure 6 ha sectional view taken substantially to on theline, 6 6;of Figure} illustrating the positionsoi the reciprocatinggair admission valve and the rotary valvewhenthe air ,ports to the air jets and to the spray nozzle are open. M

to Figure Shut showing the positions-of the valves when the air ports to the air jets are closed and the port to the spray nozzle is open.

Figure 8 is a vertical sectional view through the casting, taken substantially upon the line 88 of Figure 5.

Referring now more particularly to the drawings the reference character C generally designates the casting which forms the body or frame of the paint gun, the detailed featuresof which will be hereinafter more fully setforth, while the reference character A generally designates the leak-proof fitting which couples the inlet nozzlev receptacle is maintained firmly position through the medium of the hangerrirame Dand; the clamp mechanism E. These last'men'tioned" parts A, B, D and E are of s'tandard well-known vention, therefore, it is believed that a "more'de tailed description and, illustrationof the same are not necessary. v v I I V i j The casting C comprises the, hand grip portion i I through which an air passageway] Z'is formed, the lower end of such passageway being suitably screw-threaded to receive the eouplingnipple i3, fby means of which an air supply hose, not shown, is connected with the gun to supply air from a suitable source. v

The front side of the hand grip H is provided withfjthe upwardly opening socket [3' across the ibdt'tornior lower :end of which a pivot pin l4 ex- ,e ds to moun a tio of i see m nism as hereinafter described.

4 nected, by means of the side passage 34 which is disposed at one side of the head, with the port 21. Paralleling this passage 33 and extending upwardly through the part It of the head is a guide passage 35 in which is secured a sleeve 36 through which extends a needle valve 31, the head 38 of which is accessible from the underside of the casting head for the opening or closing of the valve. v In the upper part of the part It there is formed the cha1nber ,39.,"the outer endportionflof which is threaded as indicated at 40 and this chamber has from into the enlarged threaded portion 42 which is-axially aligned with the passage 3|.

At the-front side of the casting head portion l5 there is secured the paint spray head 43, by

means o f the' threaded stem 43' which engages construction and form no part of the present in-;-,

the threaded portion 40 of bore 39. This head 43 has the tapered forward end portion 43 through Atjhe' upper end of the handgrip, the castinfgfis formed to provide a head which is generally designated H andwhich is formed in the ,frontand rear portions l5 and I6 respectively 'which'are separatedbythe chamber H, the upper jjendiofwhich is closed by the removable cover plat'ef l8 while the lower end is open and is directeddownwardly toward the upper part of the'socket l3f.

fl3etween the upper end of the hand grip H j andtherear'partlfi of the head, is formed the t pered rotary 'valve seat I9, the rear end of Which fismteriorly threadedas indicated at 28 while the forward end leads through the short straight :fcylindrica'l portion 2| to the threaded opening 22 in which'isfitted a valve stem guide and packing assembly 23. .f';

The straight forward end portion of the rotary valve seatvhas formed longitudinally thereof the key rib 24 for the purpose hereinafter set forth. Theupper end of the air passage [2 through the handle opens into the rotary valve space 25, through the inlet port. 2.6 and in advance of this port 25 or toward the smaller end of the seat which is formed by the wall of the area 25, isan loutlet port 21 leading to the spray nozzle, hereinafter described, and a Second outlet port ,28 which leads'to the jetpassage 29 which feeds the three air jet nozzles 30 which form a part ofthe rear portion [6 of the head.' These j'ets 30 are preferably three in number and are formed or which is formed the paint discharge opening 44.

In the casting head portion l5 there are formed the'two annular channels'or passages 45 and 46 'and'the paint spray head 43 hasformed therein the forwardly leading passages 45' and '46 which, at their rear ends communicate respectively with the annular passages or channels 45 and 4E. The paint spray head, as shown, covers and closes the forward sides of'these channels 45 and 46 thus making them into closed annular compartments. .In the casting head portion I5 there are formed the two axially directed passages 33 and 33", the first of which leads directly from the passage 33 to the annular air channel 45, while the second one leads to the annular air channel 46. As shown "thesepassages 33" and 33'" are parallel andin relatively close relation and the wall between themhis-provided with-the tapered opening 33' which "forms a seat'for the'point of the needle'valve' 31, such valve extending across thepassage133 so asto have its pointed end introduced into the tapered opening 33" to conture 440i the head 43 form the paint spray nozzle and the air passage 45 leading from the channel 45 discharges at its forward end across fthe outer side of the tapered portion 43".

Overlying' and positioned concentrically with the paint nozzle is the detachable air nozzle 41 which is formed to provide the conical inner -'passage chamber 41 which le'a ds to the outlet 41" which encircles the reduced end of the portion 43" of the paint'nozzle and is spaced therefrom to providea circular opening through which airissues around the paint stream.

A portion ofthe rear end of the air nozzle 41 is co'unterbored so that'when the rear end of 'the'air' nozzle comes'irito position against the rear part of the paint nozzle there is formed the annular chamber 48 into which the air passage 45" leads. The conical interior of the air nozzle, in advance of the counterbored portion which forms the'chamber 43, co-acts with the tapered forward end portion of the paint nozzle to form the circular air chamber 48' which is in communication with the passage 45' and from whichfthe airissues through the port 41".

The chamber 48' may be identified as the fanning air chamber as it is from this chamber that the air'flows through the passages 48"" formed through the two horns 48", to be discharged from the inwardly directed jet ports 49 obliquely a'cross the path of the paint issuing from the port "44. These jet ports constitute the welllrimwn fanning or width control jets which under certain-conditions apply opposing streams of air against the paint stream so as to fiat-ten out the-paint stream in the form of a fan or brush. When'the tanning jets are shutofi by means of the needle valve 31 the paint and air spray will issue asa-con'e. i a

The air nozzle 4! is secured in place by the fastening collar or securing band 50 which threads onto the forward part of the portion l5 of the casting head. This securing band 50 is exteriorly tapered for the purpose hereinafter described. I v

-Sli'dably mounted in the opening M which is aligned with the paint receiving chamber 39, is'a reciprocable valvestem 5!, the tip or point 52' of which enters the aperture M of the spray head to close the latter under the action of a spring litwhi'ch is enclosed in the guide passage 3! and is operatively coupled with the valve stem as shown to normally urge the stem forwardly to :closedposit'ion. In the oppositeor rearend of the passage a l is threaded a tension screw 54 which tapers off rearwardly to a point as shown for streamlined w action in the air blast which flows rearwardly therearoundfromthe jet nozzles 30. As shown the paint control valve stem 5i extends across the upper part of the chamber 1? and is enclosed in and connected with a guide sleeve 55, the forward end of which forms a shoulder foriengagement by the hereinafter d'e scribed trigger lever.

"The part l5 of the casting head has a paint a passage El'i'formed therein which, at its lower end, is in communication with the tube ill while "at its upper end it opens through the port 56 into the paint chamber 39 of the spray head. Threaded into the outer end of the rotary valve chamber 25 is a bearing adjusting nut 51; This I formed between the two portions of different diameters atapered valve seat '60.

Secured in the-outer end of the tapered valve '58 is the head 6! which hasformed as an integral part thereof, the stem 52 which passes "bodies the spring 641 which constantly urges the valve 58 inwardly against the seat 19.

'Within the smaller end of the tapered valve 58 is snugly fitted theeylindrica'l slide valve t5. This valve has the tapered valve head 56 which is-adapted to position on the seat to to shut o'fi communication between the inner and outer portions of the chamber 53. Theetiter portion ofthe chamber 53 in the tapered valve 58, has 'aei-rcum ferentially directed port 5-? which is at all times in communication with the airport 26 leading from the passage E2 in the'hand grip.

Adjacent to the inner or smaller end of the tapered valve 58, there are .formed the two out- 'l'et ports 68 and 69, the port t8 "being arranged for registry with the port 23 leading to the jets 30 while the port 69 is arranged for registry with the port 21 leading to the sprayrhead "43 byway of the passages 33 and '34 and the chamber 46. As shown the port 61 is upon the opposite side of the seat from the two outlet ports 68 and B9. 7

The slide valve'65 has a recess or pocket in formed in the forward end or the end opposite from the head 66 and extending on the axial center of this valve body is a stem guide passage l l while adjacent to this passage is an air by-pass passage 12 which at its forward end opens into the pocket Tl) while its rear or back endopens into a recess 13,'the encircling wall "of which is tapered to form a valve seat 14. In addition the slide valve body has the obliquely directed-chamber 55 formed therein around the passages ll and 12. This chamber at one end opens through the wall of the valve body in close proximity to the head 66, as indicated at it, while it is divided at its opposite end to form the two ports 7i and 58 which "are locatedadja'cent to: the forward end-oi the valve. When the slide 'valve is retracted "or moved to open position the port 1 6 registers with the port '6! of'the tapered valve while the ports H and .18 register respectively with the ports 68 and 59 of the tapered valve 58, when the tapered valve inopen or partly *open position. This tapered valve 58 may be turned to a position where its port &8 will be out of registry with the air jet port: 2B,.in which case, of course, the port 71 or the slide valve WiHJTlOi) register with the port 23 when the slide valve is retracted or moved to open'position, as illustrated in Figure 7 However, the air outlet portltS of the tapered valve is of suflicient circumferential extent that even whenthe'tapered valve is turned to close off the how oft-air to the jets 3h communication will still be maintained between the supply ports 26 and bland theno'zzle'head portZi. V I v;

Extending, through the :stem -guide passage H of the slide valve is a portion of the stem 19 of antauxili'ary valve 8%. The auxiliaryvalve is in the .Zform of a poppet valve and is adapted to position :on the seat M of the slide valve while the opposite end portion of the stem extends into the guided! which is formed axially in the headed A spring 82 has one end connected with the head ti and engages against the rearward side of. the valve 89 to force the latter onto its sseat. V l I a v The forward end of the valve stem 19 extends into the pocket 7-0 and is contacted by a trigger stemtS-which extends through the guide and packing assembly 23, into the lower part of the space H of-the casting head. The :pack- ,ing of the assembly 23 prevents escape ofair from pocket l0, around stem 83.

"Thenumeral 84 designates the auxiliary trig- :ger which, as shown, risiof substantial length and its lower end extended downwardly into the socket is where it is pivotally secured by the pivot pin M. This auxiliary trigger extends across the outer or forward end of the trigger stem 83 and its upper end extends to the upper partzof the :spac'e ii-and is slotted or bifurcated as indicated at 85 to receive or straddle the paint valve 3176111151. 'llhis bifurcated upper end :of the auxiliary trigger is normally spaced forwardly of the shoulder forming guide 55 in which the -stem =51 is secured. It will thus be seen that a slight amount of oscillation is permitted the auxiliary trigger 8d before the upper end of the trigger willv'en'gage the sliding guide member 55and sense the stemti to be retracted for the :discharge of paint through the nozzle. a

Pivoted in the forward part of the space I! between the sidewalls of the casting head, at 89, is the trigger 81.

As shown the trigger 87 extends downwardly in front of the auxiliary trigger 84 and terminates in a plane above the top of the socket portion It in which the auxiliary trigger is pivotally disposed. The rear side of the trigger 81 is suitably formed for rocking or camming engagement against the auxiliary trigger 84 so that when'the trigger 81 is pulled rearwardly the desired rocking movement will be transmitted to the auxiliary trigger 84 to cause movement of the several valve parts- The paint spray collector of the present invention consists of three main parts which are, the filter unit or filter bell generally designated 88, the intermediate portion or bell and funnel connector generally designated 89, and the rear part or air funnel which is generally designated 99.

The filter bell is, as its name implies, a body of substantially bell-like form, comprising the spaced inner and outer walls 9! and 92 respectively which are maintained in the desired spaced coaxial relation by the spacer bars or rods 93 and 94.

The outershell or wall 9! of the bell terminates in the annular band 95 at its smaller end while at its larger end it is provided with an aperture 96 which leads through the threaded nipple 91 to' which is detachably connected the drainage receptacle 99.

The inner shell terminates at its small end in the collar 99 which is press fitted to and encircles the tapered locking band or ring 59. Disposed concentrically within the inner shell 92 is the funnel shaped spray baflle I99, into the smaller end of which the spray nozzle is directed on its axial center. The smaller end of this baiile is held in place by tight engagement around the air jet horns 98", so that an air passage is provided between the horns through which air may flow from between the bafile and shell 92. The baille and inner shell are coupled together by rods 93 and 94, as shown in Figure 1.

It will be noted that in addition to the fact that the forward end of the baflle I99 is inwardly of the forward or larger end of the shell 92 as illustrated, such forward end of the shell 92 is also placed inwardly with respect to the forward end of the larger and outer shell 9|. This arrangement allows for the ample flow of the paint laden air into the space between the two shells or walls of the filter bell.

In the rear or smaller end of the filter bell there is placed, between the two spaced screen walls I92, a filtering material I93 in the form preferably of cotton or cotton waste. This filter unit in efiect forms a band or collar around the rear end of theinner shell 92 and partitions the space between the inner and outer shells.

Filling the space between the inner and outer shells 9i and 92 from the forward one of the screens l92, to the forward end of the shell, is

a coarser filtering material I94 which is formed preferably of a mass consisting of many short lengths of relatively thin aluminum ribbon, which have been twisted, corrugated or otherwise deformed and which are placed side by side, forming a built up layer from one end of the bell to the other. These are vertically positioned to facilitate drainage.

The connector 89 comprises two substantially semi-circular bodies of substantial length to cover and enclose the head portion of the casting. The

two portions of this connector are-designated I and each portion is provided along its lower longitudinal edge with a flange I99 through which suitable securing elements I91 are passed into the adjacent side of the head which is located between the two sections.

The longitudinal top edge of one section I95 is formed to provide the slot I98 and the opposing longitudinal edge of the other section forms a tongue I99 which extends into this slot.

The forward end of the connector 89 receives the annular rear end portion 95 of the filter bell wall 9! and the two parts of the connector at the front end are drawn tightly together around the band 95 by a bolt and nut I I9 which is passed through the opposed apertured ears HI. Similar ears H2 are formed at the rear ends of the parts I95 so that this rear end portion of the connector may be drawn together or constricted around the inserted smaller end of the air funnel 99.

The air funnel 99 is of tapered form, being larger at its rear end and the forward end of the funnel is finished in the annular band portion H3 which is received in the connector.

The larger and rear end of the funnel 99 is pressed to form the encircling groove H4 for the attachment to the funnel, if desired, of a. fabric duct, notshown.

As shown when the spray collector is in position upon the casting head a substantial air space will be formed through the connector around the head. and the air jet nozzles 39 will be enclosed and directed rearwardly through the air funnel, the outlets of the nozzles being disposed to form a circle around the axial center of the funnel. I

In the operation of the invention when the valve trigger 81 is pressed, movement is imparted to the auxiliary trigger 99 as previously stated and this in turn puts pressure against the shaft 83 and actuates the auxiliary valve 89. While any desired range of movement for the auxiliary valve 99 and for the auxiliary trigger 94, may be provided, it is preferred that the auxiliary valve 89 be lifted from its seat when it has shifted approximately /e4th of an inch or, rather, when the auxiliary stem 89 has been shifted to this extent by the auxiliary trigger 94. This movement of the auxiliary valve 89 will, of course, be against the pressure of the air filling the rear part of the chamber 59 of the tapered valve. When the auxiliary valve 89 has been lifted from its seat the air under pressure will flow through the by-pass passage 12 into the socket 19 in the forward end of the slide valve. This transfer of the air under pressure to the opposite end of the slide valve, balances the pressure upon the two ends of such valve, thereby permitting it to be shifted from its seat 99 with a minimum of effort.

Further oscillatory movement of the auxiliary trigger 84 causes the enlarged inner end 83 of the stem 83 to press against the forward end of the slide valve and this will be shifted approximately an th of an inch to unseat the head of the slide valve before the bifurcated upper end of the auxiliary trigger 89 is brought into operative engagement with and starts to shift the paint valve stem 5 I.

This lead of air flow over the paint flow is necessary for the proper form-ationof the spray and to have the necessary air current moving through the separator between the bell walls 9| and 92 and through the funnel 99. In this manner the waste or paint mist which does not adhere 7 to the surface being coated, will be immediately picked up and-carried offithrcugh-the filter struc-- tur The sllde valve d is, previously. stated,- of cylindrical form and the underface of the head is ground: soas to engage tightlyupon the seat 60. Thus when the slide. valve is closed leakage ofitheai-r past the same is p fi yented. 1

' .lWhensthe slide valveis shiftedor opened, the

iier lenallyn a vielffsn' ay is. des red.

more air is needed'to provide it and therefore an increase in air flow to draw off the extra paint, is necessary.

When the trigger pressure is released the spring 82 operates to re-seat the auxiliary valve 86 and the slide valve 65. When this occurs the air pressure on the supply side of the slide valve 65 augments the action of the spring 82 to maintain the two valves tightly on their seats. This arrangement allows for the use of a spring of relatively light weight or only of sufficient strength to move the valve parts into place.

In order to prevent the slide valve from turning onits axis and thereby changing the positions of the ports relative to the portsof the tapered valve 58 with which it cooperates, the forward end portion of the slide valve is provided with a key groove H5 which receives the key rib 24 formed in the wall of the straight portion of the chamber or passage 25 in which the tapered valve is positioned.

The tapered valve 58 is held tight on its seat by the spring 64. This valve adjusts the quantity of air which is permitted to flow when the slide valve is actuated and the adjustment is made through the medium of the lever 63, by turning the tapered valve 58 so that the port 68 thereof may be in full registry with the port 28 leading to the air passage 29 and to the jets 30 or the air leading to the jets may be cut down or completely .shut off as desired. The air will be proportionately graduated for the port 21 leading to the nozzle but will not be completely shut off to the paint spray air nozzle port 4?" even when the port 28 leading to the jets is completely closed.

When certain types of work are to be performed the air flow to the rearwardly directed air jets 30 i may be cut off and when this is done the waste collector 98 will not be used. For example, when the fanning adjustment valve 38 is open, air will be discharged from the jets 49 to flatten out the paint spray stream, in which case the spray may be applied by moving the device in the same manner as a brush is moved. In this case the collector unit would not be used.

A particular advantage of the present waste lmcan b us d; and 0 Spra w ll e a r a he ef re'.aiob.mav.b comp etedcasily a id qu ck y w thout in rru t na he sual activities ot-theaestabli hmmlltwi l be ea lr appa en ha he d v ce he u edwitl'i or without. the. collection head'or be l ndwhen th se. of thev ol n e i i not equ ed, he connector lie-e d the mend ma be emo ed v i When' he.aircolleotorbel1is s d't d aw the waste sprayback hroush he fi te ing mat 'ri i w lllbe s enthatwh n air is d sch r d i ii the jets :01. t erewi beset u a m veme of a through. the. filtering mass-in. a, filter bell. before the paint spray is di charged ue o the. ac t a when th trigge 61 is. fir t; depressed. a r will be permitted to 'flow to thejets 3i} beforethe forked upper end-tiotthe auxiliary trigger opens the valve 51 which permits the paint to escape from the outlet aperture 44 of the paint nozzle. Thus when the spray comes into operation any of the spray which does not adhere to the surface but is dispersed into the air, will be immediately drawn back by the air currents through the cleansing and filtering mass so that the operator of the gun will not be forced to breath in air laden with the paint as is the case in the use of the ordinary spraying device. The paint which is extracted from the air by the filtering mass will collect in the lower forward part of the outer shell of the filter bell, from which it will drain olf into the collector receptacle 98 and the paint free air will be discharged rearwardly through the funnel 90.

From the foregoing it will be readily apparent that there is provided in the present invention a spray gun and waste paint collector which may :be operated with ease and which will function to effectively remove any paint mist or spray which rebounds from the surface being coated. At the sam time the device is so constructed and arranged that it may be operated without fatigue and it does not require the connection of any auxiliary suction apparatus which would make the handling of the spray gun awkward and cumbersome.

In connection with the detachable fabric air duct it is to be pointed out that "when using fast drying paints the air duct will be used but the filtering mass is removed.

I claim:

1. In a spray gun having a spray head and a spray nozzle forming a part thereof, a waste spray collector comprising a bell-like unit having a large end and a, small end and having spaced inner and outer walls, the space between said walls being open at both ends of the unit and the space within the inner wall being open at the larger end of the unit, means at the smaller end of the inner wall portion of the unit for securing such inner wall portion to the spray nozzle for the direction of spray through the units on the axial center thereof, a relatively long air conductor connected with the smaller end of the unit at the rear end of the outer wall portion, the air conductor having a portion of said spray head therein and being open at the end remote from the unit, and means forming a part of the spray head extending within said conductor for discharging air under pressure through the air conductor away from said unit.

2. A waste spray collector fora spray gun, as stated in claim 1, in which the said means for directing air through the air conductor comprises .an air jet forming a part of the spray head, with means for delivering air to said jet in advance of the discharge of spray from the spray nozzle.

3. A waste spray collector for a spray gun.-as stated in claim 1, with means between the inner and outer walls of said unit for extracting paint from air passing between said walls, and means Lfor draining off and collecting the paint extracted 'from the air passing between the unit walls.

, 4. A waste spray collector for a spray gun, as stated in claim 1, with a relatively coarse metallic filter mass filling the space between the inner and 'outer walls of the unit, a relatively tightly packed bOdyOf fine filtering material forming a partition ibetween said inner and outer walls at th smaller fend of the unit, and a drain and collector means connected with the outer wall of the unit at the lower part thereof. ALBERT DI STEFANO.

V 12 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,013,426 Murphy Jan. 2, 1912 1,191,084 Kirby July 11, 1916 1,827,470 Harrison et a1 Oct. 13, 1931 1,899,704 Lutz Feb. 28, 1933 1,906,975 Larson May 2, 1933 1,950,779 Bramsen Mar. 13, 1934 2,035,677 Steinke Mar. 31, 1936 2,183,825 Stefien Dec. 19, 1939 2,228,226 Downs Jan. 7, 1941 2,252,200 Plummer Aug. 12, 1941 2,270,579 Chamberlin et a1 Jan. 20, 1942 2,410,532 Tessie! NOV. 5, 1946 

